<template>
    <div>
      <router-link tag="div"  to="/" class="header-abs" v-show="showAbs">
        <div class="iconfont header-abs-back">&#xe624;</div>
      </router-link>
      <div class="header-fixed" v-show="!showAbs" :style="opacityStyle">
        景点详情
        <router-link to="/">
          <div class="iconfont header-fixed-back">&#xe624;</div>
        </router-link>
      </div>
    </div>
</template>

<script>
export default {
  props: {},
  data () {
    return {
      showAbs: true,
      opacityStyle: {
        opacity: 0
      }
    }
  },
  methods: {
    handleScroll: function () {
      const top = document.documentElement.scrollTop
      if (top > 60) {
        let opacity = top / 140
        opacity = opacity > 1 ? 1 : opacity
        this.opacityStyle = {opacity}
        this.showAbs = false
      } else {
        this.showAbs = true
      }
    }
  },
  components: {},
  computed: {},
  activated () {
    window.addEventListener('scroll', this.handleScroll)
  },
  deactivated () {
    window.removeEventListener('scroll', this.handleScroll)
  }
}
</script>

<style lang="stylus" scoped>
  @import "~styles/varibles.styl"
  .header-abs
    position :absolute
    top:0.2rem
    left :0.2rem
    width :0.8rem
    height :0.8rem
    border-radius :0.4rem
    line-height :0.8rem
    text-align :center
    background-color :rgba(0,0,0,0.8)
    .header-abs-back
      color :#fff
      font-size :0.4rem
  .header-fixed
    height: $headerHeight
    line-height: $headerHeight
    font-size: 0.36rem
    text-align :center
    color :#ffffff
    background-color :$bgColor
    position :fixed
    top:0rem
    left :0rem
    right :0rem
    z-index :2
    .header-fixed-back
      width :0.64rem
      color :#ffffff
      position :absolute
      font-size :0.4rem
      text-align: center
      top: 0
      left : 0
</style>
